The understanding of fundamental processes in liquids and at the liquid/electrode interfaces of electrochemical systems is crucial for the development of new devices and technologies with higher efficiency and improved performance. However, it is generally difficult to isolate and study the component of interest in such complex systems. Additionally, ex situ analyses do not always reflect the same properties under operating conditions. Hence, operando characterization tools are required for observing related electrical and chemical processes directly at the places where and while they occur. Operando x-ray photoelectron spectroscopy (o-XPS) has been used, while the sample is imposed to DC/AC voltage stress, to record the binding energy shifts in and on liquids and their interfaces to extract local potentials, as well as many related properties specific to the application in a noncontact and chemically resolved fashion. The applications of o-XPS to low-volatile liquids shown in this review span well-defined studies of (1) electrochemical cells, (2) double-layer capacitors, and (3) electrowetting on dielectrics. The methodology and several applications selected from the authors’ recent publications are presented.

中文翻译：

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基于实验室的操作X射线光电子能谱仪，用于探测各种系统中的低挥发性液体及其界面

对液体以及电化学系统的液/电极界面的基本过程的理解对于开发具有更高效率和更高性能的新设备和技术至关重要。但是，通常很难在这种复杂系统中分离和研究感兴趣的组件。此外，异位分析并不总是能反映出操作条件下的相同特性。因此，需要使用操作表征工具来直接在发生它们的地方和同时观察相关的电气和化学过程。Operando使用x射线光电子能谱（o-XPS），同时将样品施加于DC / AC电压应力下，以记录液体及其界面中和界面上的结合能移动，以提取局部电势以及许多相关特性以非接触方式和化学解决方式特定于应用程序。这篇综述中显示的o-XPS在低挥发性液体中的应用涵盖了对（1）电化学电池，（2）双层电容器和（3）电介质上电润湿的明确研究。介绍了该方法学和从作者最近的出版物中选择的几种应用。